U.S. Pat. No. 5,560,472, granted Oct. 1, 1996, to Richard T. Gist, discloses a conveyor slat, bearing, support beam, and seal system which eliminates elastomeric seal members between the conveyor slats which have for many years characterized most of the known reciprocating slat conveyors. In the Gist system, longitudinal support beams are positioned laterally between the conveyor slats. Upper portions of the support beams provide upwardly directed, hard plastic, bearing/seal surfaces. The conveyor slats have upper side portions that overhang the bearing/seal surfaces. These upper side surfaces of the conveyor slats include depending, longitudinal beads that contact and ride on the bearing/seal surfaces. The weight of the conveyor slats, and the weight of any load on the conveyor slats, is transmitted from the conveyor slats to the longitudinal support beams. This weight transfer occurs where the longitudinal slat beads contact and ride on the bearing/seal surfaces. The contact is a substantially narrow line contact. Because the contact occurs along a relatively narrow line, a substantial force is generated which urges the longitudinal beads into a tight sealing contact with the bearing/seal surfaces where there is a load on the conveyor slats. However, because contact occurs along a relatively narrow line, the area of contact is small, resulting in the forces necessary to reciprocate the conveyor back and forth along the support beams being smaller. An object of the present invention is to provide improvements to the pressure seal system that is disclosed by U.S. Pat. No. 5,560,472, for the purpose of making it easier to manufacture and install the components of the system, and to better the ability of the system to rid itself of small particulate material during times when there is no load on the conveyor slats.
The following United States patents show some prior art conveyor systems having some superficial appearance similarity to the systems of the present invention: U.S. Pat. No. 5,088,595, granted Feb. 18, 1992, to Olof A. Hallstrom; U.S. Pat. No. 5,165,525, granted Nov. 4, 1992 to Manfred W. Quaeck; U.S. Pat. No. 5,222,592, granted Jan. 29, 1993, to Manfred W. Quaeck; U.S. Pat. No. 5,228,556, granted Jul. 30, 1993, to Manfred W. Quaeck; and U.S. Pat. No. 5,323,894, granted Jun. 28, 1994, to Manfred W. Quaeck. These patents should be carefully considered for the purpose of putting the present invention into proper perspective relative to the prior art.